Scarifier and scraper attachment for a tractor

ABSTRACT

A three-point hitch scarifier and scaper attachment for a tractor is provided, in which the scarifier teeth are retractable relative to the surface of the ground and to the scraper bucket, so as to permit alternate use of the scraper with or without the scarifying action of the teeth. Simple adjustment means are incorporated in the assembly for changing the angular position of the scraper bucket about the axis of the transverse shaft on which the scarifier teeth are mounted, so as to accommodate the attachment to different site conditions. Interchangeable hydraulic and manual control elements are provided in order that the scarifier teeth may be retracted and lowered by hydraulic means, or mechanically by hand. An over-center, or past-center, toggle linkage is included so that when the scarifier teeth are in their operational position, the linkage is forced against the frame of the attachment by the torque exerted by the teeth. A further over-center, or past-center, toggle linkage is provided in the manual control securely to hold the scarifier teeth up in their retracted position against the force of gravity. The manual control includes a handle which may be shifted to two separate leverage bite positions during the manual operation to facilitate the manual control, and to make it readily accessible to the operator seated in the tractor.

United States Patent Miller et al.

[4 1 June 24, 1975 SCARIFIER AND SCRAPER ATTACHMENT for a tractor is provided, in which the scarifier teeth FOR A TRACTQR are retractable relative to the surface of the ground I L B V N y and to the scraper bucket, so as to permitalternate mentors aurence an use of the scraper with or without the scarifymg action of the teeth. Simple adjustment means are incorpo- James D. Crook, Redlands, both of Calif.

rated in the assembly for changing the angular position of the scraper bucket about the axis of the trans- [73] Assignee: Digmor Equipment & Engineering, Van Nuys, Calif.

verse shaft on which the scarifier teeth are mounted, so as to accommodate the attachment to different site conditions.

Interchangeable hydraulic and manual control elements are provided in order that the scarifier teeth may be retracted and lowered by hydraulic means, or mechanically by hand. An over-center, or past-center, toggle linkage is included so that when the scarifier teeth are in their operational position, the linkage is forced against the frame of the attachment by the torque exerted by the teeth. A further overcenter, or past-center, toggle linkage is provided in the manual control securely to hold the scarifier teeth up in their retracted position against the force of gravity. The manual control includes a handle which may be shifted to two separate leverage bite positions during the manual operation to facilitate the manual control, and to make it readily accessible to the operator seated in the tractor.

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SCARIFIER AND SCRAPER ATTACHMENT FOR A TRACTOR BACKGROUND OF THE INVENTION Scarifier and scraper attachments for tractors are known, and are used for routing the surface of the ground and for scraping away the resulting dirt. One such attachment is described, for example, in US. Pat. No. 2,839,235 I. The attachment described in the patent is hitched to a tractor, and a plurality of scarifier teeth are mounted in retractable relationship on the attachment relative to the surface of the ground and relative to the level at which the scraper bucket engages the surface of the ground. The retractable relationship of the scarifier teeth in the prior art unit relative to the scraper bucket permits the use of the scraper bucket with or without the scarifying action of the teeth.

The attachment of the present invention is of the same general type as the attachment described in the patent. The attachment of the present invention is advantageous in that it may easily be adapted for hydraulic operation or for manual operation so that the dealer need not stock two different types of attachments. As described briefly above, the scraper bucket of the at tachment of the invention may be turned about the axis of the shaft which supports the scarifier teeth, so that the attachment may be adapted to different ground conditions. When set for manual operation. a simple off-center, or past-center, linkage is used which assures that the scarifier teeth will be securely locked when in their retracted position without the need for any extra neous locking devices and without any tendency for the teeth to fall to their operating position until the mechanism is actually released by the operator. The manual control, as also mentioned above, includes a handle which has two distinct leverage bite positions to facilitate the manual operation of the attachment.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective representation of the attachment in accordance with one embodiment of the inven tion, the attachment being shown hitched to a tractor by a three-point hitch;

FIG. 2 is a side elevation, partly in section, ofa portion of the attachment of FIG. I, taken essentially along the line 22 of FIG. 1;

FIG. 3 is a front elevation, partly in section, ofa fragment of the attachment, taken essentially along the line 3-3 of FIG. 2, the scarifier teeth in the representations of FIGS. 1-3 being in their retracted position;

FIG. 4 is an elevational view, partly in section, similar to the view of FIG. 2, but with the scarifier teeth in their lower operational position;

FIG. 5 is a side elevation, partly in section, similar to the representation of FIG. 2, but showing the linkage of the attachment connected in a different manner to change the angular relationship between the scarifier teeth and the scraper, so as to increase the penetration of the scarifier teeth into the ground, the embodiments shown in FIGS. 1-5 being controlled by a hydraulic actuator element;

FIG. 6 is a view, like FIG. 2, but with the hydraulic actuator element being replaced by a manual control linkage assembly, and with the scarifier teeth being shown in their intermediate position;

FIG. 7 is a view like FIG. 6, but with the scarifier teeth turned to their retracted position;

FIG. 8 is a view like FIG. 6, but with the scarifier teeth turned to their lowered, operational position;

FIG. 9 is a fragment of the manual control linkage, taken essentially along the line 9-9 of FIG. 8, and on an enlarge scale; and

FIG. I0 is a side section of the manual control linkage of FIG. 9 taken essentially along the line I0I0 of FIG. 9.

DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS The attachment of the invention is designated generally 10 in FIG. 1, and it is shown hitched to a trailer 12 by a three-point hitch. The hitch includes two lower hitch brackets 18, and an upper hitch link 19. The attachment includes an A frame 14 which is attached to the lower hitch brackets 18. The upper link 19 is coupled to the top of the A frame, and it may be operated by the mechanism of the tractor to turn the A frame about a pivot axis designated X. A pair of annular bear ings 16 are attached to the A frame.

The embodiments of FIGS. 1-5 are hydraulically controlled, and each includes a hydraulic cylinder 20. A pivot pin 22 couples one end of the hydraulic cylinder 20 to one end of a brace arm 28, and a pivot pin 24 couples the ram or piston of the hydraulic cylinder 20 to one end of a double lever arm 26. A pivot pin 30 couples an intermediate point of the lever arm 26 to the other end of the brace arm 28.

A transverse shaft 36 is rotatably mounted in the bearings 16. A series of scarifier teeth 38 are mounted along the length of the shaft 36, and they extend outwardly from the axis of rotation of the shaft. As the shaft 36 is turned in the bearings 16 between one angular position and another, the scarifier teeth 38 are turned between their upper retracted position shown in FIGS. 1 and 2, and their lower operational position, shown in FIG. 4.

A bracket 34 is mounted on the shaft 36, and toggle link 32 is pivotally coupled at one end to the end of the lever arm 26. The toggle link is pivotally coupled at its other end to the bracket 34. A pivot pin 40 interconnects one end of the toggle link 32 to the lever arm 26, and a pivot pin 41 pivotally couples the other end of the toggle link 32 to the bracket 34. The bracket 34 is provided with a second hole 35, and the toggle link may be pivotally coupled to the bracket 34 through the hole 35, as shown in FIG. 5. This changes the relative relationship between the scarifier teeth 38 and the lower edge of the scraper bucket 100, so as to provide greater penetration of the teeth into the ground, when so desired.

The bucket is supported in the bearings 16 by the shaft 36 which is rotatably attached to the sides of the bucket. The forward end of the bucket is coupled to the forward end of the brace arm 28 by a pin 90. The brace arm 28 has a series of holes 88 for receiving the pin 90, so that the bucket may be set to a variety of angular positions about the axis of the shaft 36 to accommodate the attachment on different ground conditions.

The top of the A frame 14 serves as a stop for the lever arm 26, when the scarifier teeth are in their operational position, as shown in FIG. 4. It will be appreciated that as the attachment is drawn by the tractor 12, the scarifier teeth 38 will exert a clockwise torque on the shaft 36. This torque tends to turn the lever arm 26 likewise in a clockwise direction. Due to the off-center relationship of the lever arm 26 and the toggle link 32 when the scarifier teeth are in their operational position of FIG. 4, the upper end of the lever arm 26 is forced against the top of the A frame 14, as the scarifier teeth exert a clockwise torque on the shaft 36, so that the force is exerted against the A frame, and no undue force is exerted on the hydraulic cylinder 20. When the scarifier teeth are in their upper position, such as shown in FIG. 2, they are held locked in that position by the normal action of the hydraulic cylinder 20.

In the embodiment of FIGS. 69, the hydraulic cylinder is replaced by a manually controlled linkage including a handle 60. The handle 60 is pivotally coupled through a pair of parallel links 44, 45 to end of the lever arm 26 by means of a pivot pin 24, and the handle is pivotally coupled to the top of the A frame 14 through a pair of parallel links 46, 48. The links 44, 45 and 46, 48 are pivotally coupled to the end of the handle 60 by a pivot pin 49. The links 46 and 48 are pivotally coupled to an aperture in the top of the A frame 14 by a pivot pin 66.

The links 44, 45 and 46, 48, form a toggle linkage which, as shown in FIG. 7, assumes an over-center, or past-center, position when the scarifier teeth 38 are in their upper retracted position, so as to hold the teeth locked in their retracted position until the handle 60 is turned in a clockwise direction to the angular position shown in FIG. 8. When the handle is turned to the position shown in FIG. 8, the lever arm 26 is again forced against the top of the A frame 14, as in the previous embodiment, so that the scarifier teeth 38 are held locked in their lower operational position as they are forced along the ground.

As best shown in FIGS. 9 and 10, the links 44 and 45 are welded together by means of a spacer 51, and the links 46 and 48 are welded together by means of spacer 50. A bracket 52 is also interposed between the links 44, 45 and 46, 48 and this bracket is welded to the spacer 54 between the links 46, 48. The bracket 52 has bifurcated end portions 52a, 52b through which the pivot pin 49 extends. The pin 49 serves pivotally to couple the links 44, 45 to the links 46, 48. The pin 49 also serves as a guide for the flattened end section 60a of the handle 60. The end section 600 is received between the links 44, 45 and it has an elongated slot 62 which receives the pin 49, and which permits the handle 60 to be moved back and forth with respect to the linkage. The links 46, 48 are pivotally coupled to the top of the A frame by a pin 66.

The handle 60 turns the linkage of FIGS. 9 and 10 about the axis of the pin 66 to set the scarifier teeth either to the locked position of FIG. 7, or to the locked position of FIG. 8. As mentioned above, the handle may be adjusted to two angular positions to facilitate the leverage operation. That is, the handle might either be positioned as shown in FIG. 10, or it may be moved to the right in FIG. 10 to withdraw its end from the opening 65 in the bracket 52, turned and then moved back into the opening 67 in the bracket 52. This gives the handle a two bite leverage action with respect to the linkage, so the operator in the tractor can change the operating angle of the handle at will to suit his convenience.

The invention provides, therefore, an improved scraper attachment in which the scarifier teeth may be retracted and locked by either appropriate manual or hydraulic means, and which includes over-center toggle linkages to lock the scarifier teeth in their operational and in their retracted positions. The operational angle of the scarifier teeth may be adjusted for greater or lesser scarifier penetration into the ground. Moreover, the angle of the scraper bucket may be adjusted with respect to the axis of the shaft which supports the scarifier teeth to adapt the attachment to different ground conditions.

While particular embodiments of the invention have been shown and described. modifications may be made. It is intended in the claims to cover the modifications which fall within the spirit and scope of the invention.

What is claimed is:

l. A scarifier and scraper attachment for a tractor, and the like, comprising:

a frame including means for coupling the attachment to the tractor;

a stop member mounted on said frame;

bearing means mounted on the frame;

a transverse shaft rotatably mounted in said bearing means;

a series of scarifier teeth mounted on said shaft at spaced locations along the length of the shaft and extending radially outwardly with respect to the axis of rotation of the shaft;

a bracket mounted on said shaft;

linkage means including a toggle link pivotally coupled to said bracket and a lever arm having one end pivotally coupled to said toggle link;

a control element coupled to said linkage means to turn said shaft in said bearing means about its axis of rotation, said teeth being turned between an operational position and a retracted position when said shaft is turned by said control element in said bearing means about its axis of rotation;

a scraper bucket rotatably attached to said transverse shaft for angular movement about the axis thereof; and

further bracket means coupling said scraper bucket to said linkage means and adjustable to set the scraper bucket at predetermined angular positions about the axis of rotation of said transverse shaft with respect to said teeth.

2. The scarifier and scraper attachment defined in claim 1, in which said linkage means includes a brace arm having one end pivotally coupled to an intermediate point on said lever arm and having a series of holes therein at the other end thereof, and which includes pin means for coupling said further bracket means to said other end of said brace arm through any selected one of said holesv 3. The scarifier and scraper attachment defined in claim 2, in which said control element comprises hydraulic cylinder means interposed between said other end of said brace arm and the other end of said lever arm.

4. The scarifier and scraper attachment defined in claim 1, in which said lever arm and said toggle link assume a past-center position with said lever arm engaging said stop member when said shaft is turned by said control element so that said teeth are in their operational position.

5. The scarifier and scraper attachment defined in claim 1, in which said first-named bracket has a plurality of apertures therein for receiving said toggle link for different angular adjustments of said shaft to adjust the angular inclination of said teeth when in their operational position.

6. The scarifier and scraper attachment defined in claim I, in which said control element comprises a manually operable handle, and a further linkage means pivotally coupling said handle to said frame and to said other end of said lever arm of said first-named linkage means.

7. The scarifier and scraper attachment defined in claim 6, in which said further linkage means includes first and second link members intereoupled to assume an over-center relationship when said shaft is turned by said handle to the retracted position of the teeth, so as to provide means for holding the teeth in their retracted position.

8. A scarifier and scraper attachment for a tractor and the like comprising:

a frame including means for coupling the attachment to the tractor;

a stop member mounted on said frame;

bearing means mounted on the frame;

a transverse shaft rotatably mounted in said bearing means;

a series of scarifier teeth mounted on said shaft at spaced locations along the length of the shaft and extending outwardly with respect to the axis of rotation of the shaft;

a bracket mounted on said shaft;

linkage means including a toggle link pivotally coupled to said bracket and a lever arm having one end pivotally coupled to said toggle link;

a manually operable control handle coupled to said linkage means to turn said shaft in said bearing means about its axis of rotation, said teeth being turned between an operational position and a retracted position when said shaft is turned in said bearing means by said handle about said axis of rotation;

and

a further linkage means pivotally coupling the handle to said frame and to said other end of said lever arm of said first-named linkage means. said further linkage means including first and second link members intereoupled to assume an over-center rela tionship when said shaft is turned by said handle to the retracted position of the teeth, so as to provide a means for holding the teeth in their retracted position.

9. The scarifier and scraper attachment defined in claim 8, in which said further linkage means includes further bracket means to permit said handle to be set at least two separate angular positions with respect to the pivotal axis of said linkage for a two-bit leverage action.

10. The scarifier and scraper attachment defined in claim 8, in which said lever arm and said link assume a past-center position with said lever arm engaging said stop when said shaft is turned by said handle so that said teeth are in their operational position. 

1. A scarifier and scraper attachment for a tractor, and the like, comprising: a frame including means for coupling the attachment to the tractor; a stop member mounted on said frame; bearing means mounted on the frame; a transverse shaft rotatably mounted in said bearing means; a series of scarifier teeth mounted on said shaft at spaced locations along the length of the shaft and extending radially outwardly with respect to the axis of rotation of the shaft; a bracket mounted on said shaft; linkage means including a toggle link pivotally coupled to said bracket and a lever arm having one end pivotally coupled to said toggle link; a control element coupled to said linkage means to turn said shaft in said bearing means about its axis of rotation, said teeth being turned between an operational position and a retracted position when said shaft is turned by said control element in said bearing means about its axis of rotation; a scraper bucket rotatably attached to said transverse shaft for angular movement about the axis thereof; and further bracket means coupling said scraper bucket to said linkage means and adjustable to set the scraper bucket at predetermined angular positions about the axis of rotation of said transverse shaft with respect to said teeth.
 2. The scarifier and scraper attachment defined in claim 1, in which said linkage means includes a brace arm having one end pivotally coupled to an intermediate point on said lever arm and having a series of holes therein at the other end thereof, and which includes pin means for coupling said further bracket means to said other end of said brace arm through any selected one of said holes.
 3. The scarifier and scraper attachment defined in claim 2, in which said control element comprises hydraulic cylinder means interposed between said other end of said brace arm and the other end of said lever arm.
 4. The scarifier and scraper attachment defined in claim 1, in which said lever arm and said toggle link assume a past-center position with said lever arm engaging said stop member when said shaft is turned by said control element so that said teeth are in their operational position.
 5. The scarifier and scraper attachment defined in claim 1, in which said first-named bracket has a plurality of apertures therein for receiving said toggle link for different angular adjustments of said shaft to adjust the angular inclination of said teeth when in their operational position.
 6. The scarifier and scraper attachment defined in claim 1, in which said control element comprises a manually operable handle, and a further linkage means pivotally coupling said handle to said frame and to said other end of said lever arm of said first-named linkage means.
 7. The scarifier and scraper attachment defined in claim 6, in which said further linkage means includes first and second link members intercoupled to assume an over-center relationship when said shaft is turned by said handle to the retracted position of the teeth, so as to provide means for holding the teeth in their retracted position.
 8. A scarifier and scraper attachment for a tractor and the like, comprising: a frame including means for coupling the attachment to the tractor; a stop member mounted on said frame; bearing means mounted on the frame; a transverse shaft rotatably mounted in said bearing means; a series of scarifier teeth mounted on said shaft at spaced locations along the length of the shaft and extending outwardly with respect to the axis of rotation of the shaft; a bracket mounted on said shaft; linkage means including a toggle link pivotally coupled to said bracket and a lever arm having one end pivotally coupled to said toggle link; a manually operable control handle coupled to said linkage means to turn said shaft in said bearing means about its axis of rotation, said teeth being turned between an operational position and a retracted position when said shaft is turned in said bearing means by said handle about said axis of rotation; and a further linkage means pivotally coupling the handle to said frame and to said other end of said lever arm of said first-named linkage means, said further linkage means including first and second link members intercoupled to assume an over-center relationship when said shaft is turned by said handle to the retracted position of the teeth, so as to provide a means for holding the teeth in their retracted position.
 9. The scarifier and scraper attachment defined in claim 8, in which said further linkage means includes further bracket means to permit said handle to be set at least two separate angular positions with respect to the pivotal axis of said linkage for a two-bit leverage action.
 10. The scarifier and scraper attachment defined in claim 8, in which said lever arm and said link assume a past-center position with said lever arm engaging said stop when said shaft is turned by said handle so that said teeth are in their operational position. 